How do I stop a brooding hen!?

My hen is brooding over nothing. Literally just sitting in the box. I go out there and pull her out several times a day, walk her to the end of the yard and make her eat and drink. She won't break and she is starting to look a bit undernourished. I have tried everything! I even tried shutting the coop after everyone was done laying but then she just kept freaking out and I don't want her to hurt herself or anyone else. Help please

There are lots of threads on breaking broodiness. I'd suggest you take a look at them. I put broodies in a mini-coop, suspended above the ground for 4 days (of course with food and water). The coop can be placed on a few bricks to suspend it above the ground. If you do not have a mini-coop, pet carrier, then a cardboard box (lots of ventilation / light holes) with chicken wire as the base would do the trick also.

My experience went like this: After her setting for 3 days and nights in the nest, I put her in a wire dog crate with smaller wire on the bottom but no bedding, set up on a couple of 4x4's right in the coop and I would feed her some crumble a couple times a day.

I let her out a couple times a day and she would go out into the run, drop a huge turd, race around running, take a vigorous dust bath then head back to the nest... at which point I put her back in the crate. Each time her outings would lengthen a bit, eating, drinking and scratching more and on the 3rd afternoon she stayed out of the nest and went to roost that evening...event over, back to normal tho she didn't lay for another week or two.

Water nipple bottle added after pic was taken.

Great article on VENTILATION, one of THEMOST IMPORTANT aspects of coop design.